EDSAC 99

A brief informal history of the Computer Laboratory

Compiled by Karen Sparck Jones
using material from the University Reporter; and from
Maurice Wilkes, David Wheeler, Roger Needham, David Hartley, and
Brian Westwood, to all of whom the compiler is grateful for
help and comments.

This note indicates some of the more memorable things in the history
of the Laboratory; it is not intended to be a full account of the
Laboratory's activities, or a formal historical record or audit.

For further historical reference see:

M.V. Wilkes, Memoirs of a Computer Pioneer, MIT Press, 1985.

IEEE Annals of the History of Computing, Special issue on the University of Cambridge, Vol 14 (4), 1992.

1936 General Board Report on the Establishment of a Computing
Laboratory (2 December) referred to `recent developments in
mechanical and electrical aids to computation' and types of
machine:
`great use is now made of them in all branches of science'
`The important feature of these machines ... is the speed
with which definite answers can be produced.'
Laboratory intended (cf later GB Report 1969) `to provide a
computing service for general use, and to be a centre for the
development of computational techniques in the University'.
1937 14 May
Founded as Mathematical Laboratory, Director Professor
J.E. Lennard-Jones (Professor of Theoretical Chemistry),
only staff member M.V. Wilkes, appointed as University
Demonstrator.
To be used for mechanical computation with a differential
analyser, desk machines, etc.
The Laboratory was to be housed in the North Wing of the
former Anatomy School, on the New Museums Site.
Not yet opened when taken over by Ministry of Supply for the war.
Wilkes already working elsewhere on radar and, later, on
operational research.
1945 Laboratory returned to civilian use, with Wilkes (temporary
University Lecturer) as Acting Director.
1946 General Board Report on the Organisation of the Laboratory
(24 July):
`the Laboratory has been equipped with a number of the most
modern calculating machines, ... and library and workshop
facilities have been built up and assistants appointed.'
`its services will be available to all departments of the
University'
`[Dr Wilkes] has formed projects of research work ... which
will be of great value to the science of computation.'
Wilkes appointed Director with `the duty to advance knowledge of
the science of mathematical computation, to promote and
direct research in it, and to supervise the work of the ...
Laboratory under the general control of the Mathematical
Laboratory Committee.'
1946 October
Work began on the EDSAC (Electronic Delay Storage Automatic
Calculator, later referred to as EDSAC 1), following Wilkes'
visit to the US in August and September.
1947 Messrs J. Lyons and Company gave a grant of 3000 pounds for
research in the Laboratory, with no attached conditions, and
support for an assistant for a year (in practice much longer).
Student volunteers, V. Hale, B. Haselgrove and D.J. Wheeler,
helping with constructional work.
1947-8 Thursday Colloquia began; first talk B. Noble on programming
for the EDSAC.
Laboratory's first research student, J.M. Bennett, followed by
D.J. Wheeler.
Laboratory members working under Wilkes and all contributing
in some way or other to the EDSAC project included academic
staff: W. Renwick, B. Noble, D.W. Willis and E.N. Mutch;
assistant staff: P.J. Farmer, G.J. Stevens, S.A. Barton,
R.S. Piggott, L.J. Foreman and P. Chamberlain; and research
students: Bennett and Wheeler.
(Laboratory assistant staff list for 1948 has 14 people, including
two unestablished `boys' and a part-time cleaner; photograph
of 1948 has 19 people.)
1948-9 Research on programming methods under Wilkes, including:
definition and refinement of Initial Orders (Wheeler); closed
subroutines (Wheeler); building of a library of subroutines
(all laboratory members interested in programming, plus
Professor D. R. Hartree).
1949 6 May
First logged program on EDSAC 1 (computing squares of 0-99).
This was the first complete and fully operational regular
electronic digital stored program computer; Manchester's
absolute first, in 1948, was the Small Scale Experimental
Machine, built to validate innovative CRT memory
technology. (These machines were before the first US machines.)
Normal operation, with paper tape input, for range of user
calculations. The Initial Orders, (a primitive assembler)
were hard wired on to rotary telephone switches.
June
Conference on high-speed automatic calculating machines,
first outside US, with 100 participants; EDSAC 1 demonstrated
and came out very well. (Report published 1950, later
version, edited by M.R. Williams and M. Campbell-Kelly, in
MIT/Tomash historical series, 1989.)
General Board report on the Organisation of the Laboratory
(19 July):
`the Laboratory has developed until it now occupies a leading
position among the mathematical laboratories of the country.'
It has `calculating machines ... Hollerith equipment ... and
a high speed electronic calculating machine has been designed
and largely constructed in the Laboratory. The work on this
machine has already won recognition and financial support
for the Laboratory from outside sources.'
Laboratory therefore freed from its Committee; Wilkes
became Head of Department and Renwick (chief engineer) a
University Demonstrator.
1950 Program service began on semi-formal basis, with an operator to
run programs (except at night, when authorised users were
entitled to run the machine till it broke, a tradition continued
with EDSAC 2); early operators included E. Breakwell (in the
1951 film), V. Webber, R. Hill.
Significant development of library routines, e.g. S. Gill's
Runge Kutta program, Wheeler's interpretive floating point
routine. Interpreter by Bennett to allow compact programs.
First steps in computation for X-ray crystallography also by
Bennett.
First Summer School on Programme Design for Automatic Digital
Computing Machines, with 51 attendees (they ran till 1958).
Further research students working in the Laboratory (4 listed in
1950) included Gill, A.S. Douglas, B. Worsley, E.S. Page.
University staff 4: Wilkes, Renwick, with R.A. Brooker and Mutch
Assistants in Research.
Others outside the Laboratory also involved with EDSAC 1,
notably Professor Hartree.
1951 Film made of EDSAC 1.
`The preparation of programs for an electronic digital computer'
by Wilkes, Wheeler, and Gill, Addison-Westley, the first book
on programming to be published.
LEO computer, world's first business computer, developed by
Lyons and based on EDSAC 1, began operation.
Wilkes' paper, `On the best way to design an automatic calculating
machine', introduced the idea of microprogramming and
bit-slicing.
Work began on EDSAC 2, with a grant from Nuffield Foundation.
1952 Magnetic tapes introduced experimentally for EDSAC 1.
1952 onwards
Continuing development of programs and methods e.g. hash tables,
recursion with stack, program labels (Wilkes), Fourier
transforms.
1953 Diploma in Numerical Analysis and Automatic Computing began
(``automatic computing'' then best shot at ``computer science'');
one-year postgraduate course, the first formal course
leading to a university qualification anywhere in the world.
Motivated by Mathematics Faculty Board Report on the
`demand for postgraduate instruction in numerical analysis and
automatic computing ... [which] if not met, there is a danger
that the application to scientific research of the machines
now being built will be hampered'.
The Laboratory `was one of the pioneers in the development and
use of electronic computing-machines (sic)'.
`The Summer School deals [only] with ``programming'', rather
than the general theory of the numerical methods which are
programmed.'
The Diploma `would include theoretical and practical work ...
[and also] instruction about the various types of computing-
machine ... and the principles of design on which they are
based.'
With only a few students initially, no extra staff would be
needed.
University-supported teaching and research staff in the Laboratory
were Wilkes, J.C.P. Miller, Renwick, Mutch, and Gill, joined
slightly later by C.B. Haselgrove.
1953 onwards
Heavy use of EDSAC 1 for (among other subjects) theoretical
chemistry under S.F. Boys; X-ray molecular biology by
J.C. Kendrew; numerical analysis by Hartree, Miller;
atmospheric oscillations by Wilkes; early work on
radioastronomy (much extended on EDSAC 2) by group under
M.F. Ryle.
Priorities Committee established for approval of computing
projects and resource allocation.
1954 Diploma 2 written papers and 1 3-hour practical (4 hours 1955).
3 successful candidates.
1956 As many as 100 attended the Summer School.
1956-7 EDSAC 1.5, (EDSAC 2 with Wheeler's small control matrix, precursor
of EDSAC 2), running and used by J. Blackler (later J. Wheeler)
for astrophysics.
1958 EDSAC 2 taking load from EDSAC 1.
11 July
EDSAC 1 shut down.
EDSAC 2, the first full-scale microprogrammed machine, also
the first bit-sliced machine. Used fast paper tape for I/O,
magnetic tapes. A small number of basic library subroutines
were wired into a ROM.
1960 University-supported academic staff now 6, Wilkes, Wheeler,
Miller, H.P.F. Swinnerton-Dyer, Mutch, and Mrs M.O. Mutch.
Total staff estimated about 30 including about 10 engineers.
About 7 PhD students and 10 Diploma students.
Number of users unknown, but at least 50 (a lot for those days).
1961 Autocode for programming, developed by D.F. Hartley, following
stimulus from Manchester, in service.
Business game, implemented by J. Hillmore (a Diploma student);
attractive application with many takers, eg Her Majesty's
Treasury.
Proposal for TITAN, modified version of ATLAS then being
developed by Ferranti. W. S. Elliott joined the Lab as Senior
Project Engineer. Joint project with Ferranti and successor
companies (ICT and ICL); some automated hardware design done
at Cambridge; operating system developed jointly.
Designed originally for multi-processing; design modified
after Wilkes' visit to MIT in 1963 to support multiple-access
(provision for up to 64 terminals).
Had slave store - nowadays instruction cache (Wheeler); was
also designed for very rapid response to interrupts, with more
operating system scheduling than was then usual.
N.E. Wiseman became Chief Engineer.
Work on design of CPL, a higher-level language intended for TITAN,
initiated by Hartley and D.W. Barron; C. Strachey later joined
the project, and the then University of London Institute for
Computer Science became involved. A seminal project.
1962 Large (16 K words) memory addition to EDSAC 2.
1964 TITAN came into service with first operating system (Temporary
Supervisor by Swinnerton-Dyer). Magnetic tapes.
1965 EDSAC 2 switched off.
Autocode, first higher-level language on TITAN. Followed
later, under pressure from scientific users, by Fortran.
Fifteen years of CAD research, initially led by C.A. Lang, began,
using a PDP 7 and DEC Type 340 display (the first outside
the USA) connected by data-link to the TITAN. It later
involved a highly innovative numerically-controlled
machine for cutting models of metal parts in plastic foam.
Diploma renamed Diploma in Computer Science.
1966 TITAN Main Supervisor replaced the Temporary Supervisor.
1967 TITAN multiple-access system on a 24-hour, 7-days-a-week basis
to users outside the Laboratory (film of system made in 1968).
Discs had been installed to support this.
R.M. Needham originated and installed now almost universal
practice of storing passwords with one-way function; also a
quota system for allocating file storage.
1968 M. Richards returned from MIT and continued work on BCPL, a
language with roots in CPL he had developed, and an ancestor
of the still widely used C.
Vigorous growth of computing service under the Superintendent,
E.N. Mutch; about 200 users of the multiple-access system.
Line of work on automated algebra began under D. Barton,
carried on by J.P. Fitch, (Adams Prize 1975), S.R. Bourne
and A.C. Norman.
1969 Move to new (present) building on an adjoining site. TITAN
airlifted by crane (`the computing service is suspended').
Service maintained for three months using another ATLAS 2
at CAD Centre (Ministry of Technology).
Sad early death of E.N. Mutch, while move was in progress.
General Board Report on the Laboratory and University Computing
Service (22 October):
`from the very beginning EDSAC 1 was made available to anyone
in the University who could make good use of it; and such users
were able to obtain advice and assistance from ... the
Laboratory.'
`the steady improvement ... of TITAN has enabled it to meet
the steadily increasing needs of the computing service,
providing in the process the first substantial multiple
access system to be available in a British University.'
`Over the last twenty-five years the ... Laboratory has
become a service department comparable only with the University
Library', imposing a heavy burden on the staff.
Major reorganisation followed.
Research on screen editing under Wiseman using the PDP 7.
1970 Laboratory teaching, research and technical staff 24,
including externally funded (and only 1 Lecturer). Total
staff 75.
About 27 PhD students, 21 Diploma.
Mathematical Laboratory renamed Computer Laboratory, became
institution independent of any faculty, responsible to
the Computer Syndicate.
Computing Service divided from teaching and research within
Laboratory. D.F. Hartley became first Director of the
University Computing Service.
1970-77 CAP project on memory protection, based on capabilities
implemented in hardware, under Wilkes and Needham with
Wheeler responsible for implementation (BCS Technical
Award 1978 for `CAP (Capability Protection) Project' to
Needham).
1971 One-year Computer Sciences Tripos, first independent
undergraduate teaching (started one year earlier as a Part II
within Natural Sciences Tripos, though computing was not
deemed an experimental subject), 34 students.
Diploma and Tripos each 4 exam papers.
IBM 370/165 installed for the Computing Service.
S.A. Barton became Chief Engineer after Wiseman became Lecturer.
1972 Wiseman seconded to the Cambridge University Press for
the development of a computer-aided type setting and book
production system; very successful.
1973 TITAN switched off.
IBM memory doubled from 1Mbytes to 2, file store 1000Mbytes; PDP 11
communications front end for 10 Remote Job Entry stations, 133
terminal lines; interactive graphics unit based on a PDP 11;
three-shift operation, two outstations.
Computing Service established staff 26 plus 5 engineers.
About 2500 users.
1974 Cambridge RING project initiated, involving many people;
National standard 1982.
Shape Data Ltd started, probably the Laboratory's first spin-off
company.
1975 Phoenix Command Language for IBM 370/165.
1977 Initial work on University Data Network as a service,
independent of the mainframe computer.
Beginning of formal project, under the Government's Advanced
Computer Technology Projects, to develop a chip implementation
of the Cambridge Ring. Led to research in electronic CAD.
1978 Two-year Computer Science Tripos began.
Research on Cambridge Model Distributed System began.
1979 University-wide hardware maintenance service formalised and
expanded.
A. Hopper appointed an Assistant Lecturer.
1980 Professor M.V. Wilkes retired. Succeeded as Head of Department by
R.M. Needham.
M.J.C. Gordon joined the Laboratory from Edinburgh University and
inaugurated a new line of research in formal methods.
Teaching and research staff 10. Computing Service established
staff 31, plus 6 engineers. Total Laboratory staff 98. Also
about 10 postdoctoral research fellows and assistants.
43 PhD students, 15 Diploma, 98 Tripos.
About 1400 active users.
Service 368 communication links, 3 outstations.
Development work on Fast Ring begun.
1980 onwards
Major research projects included formal verification of hardware
designs (Gordon); Project UNIVERSE, interconnection of LANs by
satellite (Needham, A.J. Herbert and I.M. Leslie); Rainbow
display (Wiseman) (BCS Technical Award 1985 for `The Cambridge
Rainbow Display' to Wiseman).
[R.M. Needham : ``halcyon days'' - an expanding Laboratory and no
external interference.]
Expansion of mass teaching in programming, led by F.H. King.
Creation of Supporters Club led by J.A. Lang, by mid-90s having
several dozen companies including many with personal origins
in or links with Laboratory students or staff.
Continued takeover of accommodation (laboratory came to extend
from Corn Exchange Street to Free School Lane, via 2 bridges!).
1981 BCS Technical Award to the Computer Laboratory for `The Cambridge
Digital Communication Ring'.
1982 IBM 370/165 replaced by IBM 3081D.
Development of `JNT-PAD', microcomputer network unit building
block for university X.25 networks in U.K.
UNIX system on VAX 11/750 as second service within Laboratory;
but also gradual transition during 80s for research side to have
its own machines.
1983 Major expansion of Laboratory (teaching and research) with
5 new posts.
1985 One-year MPhil in Computer Speech and Language Processing, jointly
with Engineering Department. Consolidation of research on
natural language processing (K. Sparck Jones, S.G. Pulman).
Verification of VIPER chip (Gordon and A. Cohn).
Line of research on middleware began (J.M. Bacon, K. Moody).
1985 onwards
Collaboration with nearby industrial research establishments,
especially SRI International and Xerox Europarc.
1986 Project UNISON, distributed systems (Leslie).
Link with Olivetti Research Laboratory (ORL) established.
1987 50th Anniversary of the Laboratory.
1987 onwards
Further development of research on authentication and security
(Needham).
Work on theorem proving, e.g. Isabelle (L.C. Paulson).
Computing Service adopted Granta Strategy to promote distributed
computing: based on Granta Backbone Network, optical fibre
cabling across University and colleges, and combining
mainframe with other computers and personal machines.
1989 Full 3-year Computer Science Tripos began.
IBM 3081D upgraded to 3084Q; Automatic Cartridge Store.
1990 Teaching and research staff 27. Computing Service established
staff, including engineers, 44. Total Laboratory staff 127.
About 30 postdoctoral research fellows and assistants.
92 PhD students, 33 Diploma, 170 Tripos, 19 MPhil.
About 6500 active users.
1990 onwards
Increasing emphasis on multimedia computing.
1992 Granta Backbone Network completed (a political achievement for
Hartley as well as technical achievement by him and his team).
1993 Cambridge Honorary Degree for Wilkes.
Autostereo display (Wiseman and S.R. Lang).
1994 Hartley succeeded as Director of Computing Service by
M.D. Sayers.
Professor D. J. Wheeler retired.
1995 N.E. Wiseman, an early worker in the laboratory, later Chief
Engineer and subsequently on the teaching staff, died in
service.
IBM 3084, last general-purpose mainframe in the Laboratory,
decommissioned.
1995 A.J.R.G. Milner appointed to Laboratory's first established
chair; succeeded Needham as Head of Department in 1996.
1996 Hitachi SR2201 parallel machine housed in Laboratory.
1997 Research Assessment Exercise Grade 5* (top, as in previous
three).
Link with Cambridge Microsoft Research Laboratory.
William H. Gates III Foundation benefaction for new building.
BCS Award 1997 for `Iris Recognition' to J.G. Daugman.
1998 Main lines of research during 90s:
theory and formal methods, theorem proving;
compilers, interpreters, and program analysis;
distributed systems and communications, multimedia;
database structure and systems;
security, authentication and privacy;
graphics and animation (including 3D display);
natural language and information processing;
vision and image processing.
Many and varied collaborative connections with industry, other
universities, etc, in UK and abroad; continued input to
local startup companies.
Teaching and research staff 29. Computing Service established
staff, including engineers, 54; full staff 93. Total
Laboratory staff 134. About 35 postdoctoral research fellows
and assistants.
105 PhD students, 42 Diploma, 259 Tripos, 22 MPhil.
About 24000 registered users: `everyone in the University and
then some' (Unix service 5000 users, mail service 22000,
workstation filestore 9000).

Past members of the Laboratory are now be found in prominent positions
all over the US and the UK, in companies and universities. Honours for
members of the Laboratory have included two Turing Awards and fellowships
of the Royal Society, the Royal Academy of Engineering and the British
Academy.

The above is version 5.3 of the History, reflecting its state on 1 April 1999, at the time of the EDSAC 99 celebration.

1999 I.M. Leslie becomes Head of Department.
2001 Computer Laboratory (teaching and research) formally separated
from the Computing Service.
Computer Laboratory moved to new William Gates Building in
West Cambridge.
2004 A. Hopper becomes Head of Department.